An Egyptian court has sentenced three Al-Jazeera English journalists to three years in prison.

The court issued the verdict on August 29 in the long-running trial criticized worldwide by press freedom advocates and human rights activists.

The three Al-Jazeera journalists -- Canadian national Mohammed Fahmy, Australian journalist Peter Greste, and Egyptian producer Baher Mohammed -- were detained in December 2013 while working for the Doha-based network.

The three first were sentenced to prison before Egypt's highest court ordered a retrial on charges of them allegedly being part of the Muslim Brotherhood, which authorities have declared a terrorist organization, and airing falsified footage intended to damage national security.

Egypt deported Greste in February.

Fahmy and Mohammed, who had been released on bail, were present at the August 29 sentencing and taken away by police after the hearing.

Lawyers for the three journalists are expected to appeal the decision.

In the courtroom in Cairo on August 29, Judge Hassan Farid said the court has investigated the case fully and established that the three had broadcast false news, were not journalists, and operated without permits or licenses.

Three Egyptian students on trial alongside the journalists were also jailed for three years.

One of the three Al-Jazeera English journalists -- Egyptian producer Baher Mohammed -- will spend another six months behind bars for possessing a "bullet," according to Egypt's state news agency MENA.

Greste said he was "shocked" at the scale of the sentence, while Al-Jazeera English acting Director-General Mostefa Souag said the verdict "defies logic and common sense."

Canadian Minister of State for Consular Affairs Lynne Yelich said the court's decision "severely undermines confidence in the rule of law in Egypt."

Amnesty International also condemned it as well, calling the sentences the "death knell for freedom of expression in Egypt."

The three denied all charges and rights advocates said their arrest was part of a wider crackdown on free speech since the military overthrew President Muhammad Morsi, a senior Muslim Brotherhood figure, in mid-2013 following mass unrest.